A 2-day-old male presents with cyanosis, tachypnea (RR 58/min), and poor feeding. Vital signs show HR 165/min, BP 62/38 mmHg, SpO2 78% on room air, and temperature 37.2°C. He has hepatomegaly but no murmur. Chest X-ray demonstrates cardiomegaly with increased pulmonary vascular markings. Echocardiography reveals a single arterial trunk arising from the heart with a large ventricular septal defect. Which embryologic mechanism best explains this presentation?

  1. A)Failure of the aorticopulmonary septum to formGABARITO
  2. B)Premature closure of the ductus arteriosus
  3. C)Underdevelopment of the left fourth aortic arch
  4. D)Failure of the tricuspid valve to canalize
  5. E)Failure of the septum primum to close the foramen ovale

Explicação

Persistent truncus arteriosus results from failure of neural crest derived truncal ridges to form the aorticopulmonary septum. A single outflow tract persists and is commonly associated with a ventricular septal defect. The lesion causes mixing of oxygenated a... Ver explicação completa e trilha adaptativa →

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